Plz help solve this please and thx u

Mathematics

1 answer:

kow [346]2 years ago

3 0

2 (an - 1) = 40
2an - 2 =40
2an = 40 - 2
2an = 38
2an/2 = 38/2
an = 19

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X 0 2 10 20

prisoha [69]

Use two points from the graph to check if they are constant. In this case let’s use (0,50) & (2,58)

To find slope you have to do the following.

y2-y1 / x2-x1

Plug in the values, 58-50/2-0
This gives you 4.

When you use two other points, in this case (10,90) (20,130) you get a slope of 4.

This means the slope is 4.

We are trying to get an equation of y=mx+b.
We have slope already which is 4. So now we plug in y=4x + b

Now we need to find b. There is an equation to solve for b. Which is b=y1-m(x1)

But b is the y-intercept so there is already a B which is 50

So the table IS a linear equation and the equation is y=4x+50.

8 0

2 years ago

Directions for questions 4 & 5: We selected a random sample of 100 StatCrunchU students, 67 females and 33 males, and analyz

GaryK [48]

Answer:

The 95% confidence interval for the difference between means is (-2164.21, -299.13).

The lower limit on the confidence interval is -$2164.21.

The upper limit on the confidence interval is -$299.13.

Step-by-step explanation:

The sample data is:

Gender Mean Std. dev. n

Female 2577.75 1916.29 67

Male 3809.42 2379.47 33

We have to calculate a 95% confidence interval for the difference between means, with a T-model.

The sample 1, of size n1=67 has a mean of 2577.75 and a standard deviation of 1916.29.

The sample 2, of size n2=33 has a mean of 3809.42 and a standard deviation of 2379.47.

The difference between sample means is Md=-1231.67.

$M_d=M_1-M_2=2577.75-3809.42=-1231.67$

The estimated standard error of the difference between means is computed using the formula:

$s_{M_d}=\sqrt{\dfrac{\sigma_1^2}{n_1}+\dfrac{\sigma_2^2}{n_2}}=\sqrt{\dfrac{1916.29^2}{67}+\dfrac{2379.47^2}{33}}\\\\\\s_{M_d}=\sqrt{54808.468+171572.045}=\sqrt{226380.513}=475.795$